A detector in Antarctica discovers long-sought-after evidence to back up the theory of inflation following the big bang.

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Today, scientists at the Harvard-Smithsonian Center for Astrophysicsannounced they've found evidence of the big bang that they've been seeking for decades: gravitational waves in the cosmic microwave background (CMB). The research team at the BICEP2 facility in Antarctica made the discovery, which not only backs up the inflation theory behind the big bang in which the universe expanded rapidly right after its birth, but also will shape our understanding of physics and the origins of the universe for years to come.

In 1916, as part of his General Theory of Relativity, Albert Einstein predicted gravity waves would emerge as a result of the rapidly expanding universe. The BICEP2 scientists saw quantum movements in the CMB indicating oscillating waves of gravity. If this discovery is confirmed, it will be the first direct evidence of them.

In a blog post in advance of the announcement, Caltech researcher Sean Carroll said, "Other than finding life on other planets or directly detecting dark matter, I can't think of any other plausible near-term astrophysical discovery more important than this one for improving our understanding of the universe."

The waves reach back—way back—to just 380,000 years after the big bang, when the universe burst forth in all directions from a single point of infinitely dense energy. "The CMB is a snapshot of the Universe 380,000 years after the big bang, when the radiation first streamed freely into space," lead researcher John Kovac said in an interview with Nature. "But the gravitational-wave signal was imprinted on the CMB a tiny fraction of a second after the birth of the Universe."

Despite all the evidence backing up the theory of the big bang and cosmic inflation, flat-out proof of those gravity waves had eluded physicists for years. BICEP2, like its predecessor, was designed to measure polarization in the CMB, searching for B-modes and other evidence of the big bang theory, specifically in regard to the inflation of the universe. The BICEP2 researchers found that evidence, and at a higher-than-expected strength: 1016 gigaelectronvolts. Clem Pryke of the University of Minnesota compared the find to looking for a needle in a haystack, "but instead we found a crowbar."

Specifically, the researchers were looking for B-modes. These are curls and twists in visible light that can be created only by gravitational waves. The research focused on a patch of the CMB relatively free of dust or radio interference from our galaxy, narrowing the possibility of cosmic contamination of the results.

Studying these waves could lead to landmark discoveries as part of physicists' mission to unify quantum and classical mechanics.

"Inflation assumes that everything started out as quantum fluctuations that then got amplified by inflation," Kovac said. "So at a very deep level, this finding relies on the connection between quantum mechanics and gravity being right."